1. Field
Methods and apparatuses consistent with the exemplary embodiments relate to a channel adaptive video transmission method, an apparatus using the same, and a system providing the same, which adopts an SVC encoding method that can provide an optimum seamless transmission of a high picture quality digital video stream to a user by using state information of a network and a corresponding mobile terminal in a variable wireless environment.
2. Description of the Related Art
In general, with the development of information and communication technology including the internet, video communication has been increasing in addition to text and voice communication. The existing text-centered communication method is insufficient to satisfy diverse desires of consumers, and accordingly, multimedia services that can accommodate various types of information, such as text, image, music, and the like, have been increasing. Multimedia data have massive quantity, and require large-capacity storage medium and wide bandwidth during transmission. Accordingly, in order to transmit the multimedia data including the text, video, and audio, use of a compression coding technique is required.
Scalable video coding (SVC) that is H.264 scalable coding technology is a new scalable coding technique developed to simultaneously solve the problems of low compression efficiency, impossibility of complex scalability support, and high implementation complexity, which are drawbacks of the layer coding based scalability attempted by MPEG-2, MPEG-4, and the like.
The SVC video coding means a coding method which can adjust a video resolution, frame rate, signal-to-noise ratio (SNR), and the like, of a compressed bit stream by cutting a part of the bit stream in accordance with the peripheral conditions such as a transmission bit rate, transmission error rate, system resources, and the like, that is, a coding method which supports diverse scalabilities.
The SVC encodes several video layers into one bit stream. The SVC layers include one base layer and scalable layers that can be continuously filed up on the base layer. In this case, the respective scalable layers have maximum bit rates given thereto based on lower layer information. The respective scalable layers can express the maximum bit rates, frame rates, and resolutions given thereto based on the lower layer information.
Since the SVC can support diverse bit rates, frame rates, and resolutions as many scalable layers are continuously filed up, problems of diverse bandwidths occurring in a heterogeneous network environment, problems of diverse performances and resolutions of a receiving terminal, problems of diverse preferences of content consumers, and the like, can be compositely solved:
FIG. 1 is a view schematically illustrating the configuration of the whole system that provides a video transmission service in the related art. Referring to FIG. 1, the system includes a wireless network 110, a server 112 connected to the wireless network to perform a data service, and a plurality of mobile terminals 114, 116, and 118 communicable with the server 112 through the wireless network 110.
As illustrated in FIG. 1, a corresponding service, once connected to the network through the wireless network 110, can provide only a corresponding service.